Many facilities have protocols in place to comply with health, safety, insurance, and regulatory requirements. In large facilities, such as factories and hospitals, there may be a large number of people, equipment, areas, and other resources that need to be tracked in the enforcement of protocols. In addition to the large numbers involved, there may also be many different types of people, equipment, areas, and resources in such large facilities. Each of the different types of people, equipment, areas, and resources may have different types of associated protocols.
As an example of a compliance protocol, there may be specific areas or zones in a facility that only qualified personnel are allowed to access. In factories, these compliance zones may be hazardous zones where dangerous equipment or chemicals are used, and that only qualified personnel with appropriate safety gear are allowed to access. The level of qualification required for a zone may range from requiring a hard-hat when in the zone to requiring a protective suit and respirator when in the zone. Facilities may also have other zones, such as clean rooms and secure rooms, where certain protocols must be observed. Access to these zones may require personnel to have specific training or security clearance or to take certain actions when entering, exiting or remaining within the zones.
Hospitals also have to regularly monitor and enforce numerous protocols that vary with the different types of people (non-employee and types of employees), equipment, areas, and resources involved. At any given time, in addition to the medical professionals, administrative staff, and housekeeping staff, there are a number of patients, visitors, consultants, contractors, and the like, in the hospital. Each of these individuals may have different protocol requirements associated with them. Hospitals may also have several areas with specific protocol requirements, such as, patient rooms, laboratories, surgical theaters, clean rooms, intensive care areas, quarantined areas, radiology, record rooms, administrative offices, data and security centers, medical supply rooms. Each of these areas may require different protocols. Hospitals may also require the use of temporary or non-permanent protocols. For example, a protection protocol may be required for a specific patient or piece of equipment. A patient or bed holding a patient may be designated as contagious, and only appropriately qualified and equipped medical professionals may be allowed in proximity of the patient or bed. In some circumstances, medical professionals may be required to comply with typical or atypical protocols, such as the use of an N95 respirator when in proximity of patients with certain diagnoses or the need for washing hands when exiting a compliance zone. Other protocols may be generic to a type of person or area.
Enforcement of even simple protocols may be difficult when dealing with a large and busy facility like a hospital, and real time enforcement may be extremely difficult. An exemplary hospital protocol is a hand hygiene or hand washing protocol. Studies indicate that proper adherence to hand hygiene protocols can significantly reduce morbidity and mortality rates caused by hospital-acquired infections. However, enforcement of the behaviors specified in hand hygiene protocols can be difficult in a hospital due to the large number of individuals requiring monitoring and the generally busy fast-paced environment inside a hospital.
Some techniques of monitoring compliance with protocols involve establishing zones within the facility in which each zone has particular protocols associated with it. For example, a clean zone around a patient's bed may require a hand washing protocol to prevent contamination of the clean zone. These techniques monitor interactions of a resource, e.g. hospital staff, with a zone to determine whether the resource has complied with a protocol associated with the zone.
Some conventional techniques of establishing a zone involve transmitting infrared (IR) signals to designate the boundaries of the zone. Infrared signals are line-of-sight (LOS), i.e. the signals propagate in a straight line and generally cannot travel through or around obstacles. Infrared is suitable for some conventional zone-establishing systems because infrared signals do not penetrate walls and can be contained within well-defined zones.
However, there are significant drawbacks to conventional techniques of establishing zones with the transmission of infrared signals. Generally, conventional systems do not work if the line-of-sight between an infrared transmitter and an infrared receiver is blocked, e.g. if a receiver badge worn by a clinician is covered by the clinician's clothing or the protective garb that is required to be worn in certain patient rooms. As such, infrared signal receivers on clinician-worn badges must always be exposed outside the clothing. This often requires uncomfortable or undesirable placement of the badges, e.g. at the back of the neck or shoulder. Exposure of the badges outside the clothing also breaches the infection control barrier of the clothing, which makes the infrared receiver badges unsuitable for use in clean areas. Hospital staff-members wearing infrared receiver badges thus need to be conscious of how and where they wear the badges. For similar reasons, infrared transmitters that indicate use of a hand-washing station cannot be integrated into a hand-washing dispenser because the infrared signals do not penetrate the dispenser casing.
Infrared signals are also susceptible to shadowing, which occurs when an obstacle obscures the main signal path between the infrared transmitter and receiver. Conventional techniques attempt to overcome the problem of shadowing by using a large and complex set of infrared transmitters to establish a single zone. These conventional techniques are expensive to install and require an extensive infrastructure.
Other conventional techniques of establishing a zone involve transmitting radio frequency (RF) signals or Radio Frequency Identification (RFID) signals to designate the boundaries of the zone. Radio frequency signals are not line-of-sight and can generally travel through or around obstacles. This characteristic allows radio frequency receivers, e.g. on clinician-worn badges, to reliably receive signals from a radio frequency transmitter substantially regardless of the topography of the zone. However, this non-line-of-sight characteristic also means that the radio frequency signals can penetrate walls, and cannot reliably be contained within zones that are defined between a set of walls. For example, a radio frequency signal transmitting in a room to define a zone within the room may be received by radio frequency receivers outside the zone in adjacent rooms. Thus, in these conventional systems, a radio frequency receiver may have difficulty in identifying the source of a received signal.
Despite the above shortcomings, both infrared and radio frequency signals have served as preferred technologies for establishing zones over other technologies such as ultrasound. This is because ultrasound signals are typically not suited to sending large amounts of data. In addition, ultrasound signals are often prone to multipath interference, a phenomenon whereby a wave from a source travels to a detector via two or more paths and, under the right conditions, the two or more components of the wave interfere.